The flexible bladder expansion tank is required to maintain circulated water loop design pressure over a wide range of water temperatures.
Tank is preset at 12 psi, and has an air valve to adjust pressure as needed.
Tank may be installed horizontally or vertically. It should be piped into the suction side of the circulation pump, typically at the same location as the fill assembly. Tank connection is 1/2" male NPT.
Required expansion tank size is based on the total air handler capacity. Capacities of 120,000 to 720,000 BTU/hr are available.
See the spec sheet for complete technical details.